<span>A.The amount of time it takes for half of the material to decay</span>
The difference between natural dye and synthetic dyes is largely that synthetic dyes are chemically manufactured whereas natural dyes are purely developed from nature.
To get the melting point of a solution so, we will use this formula:
ΔT = - mKf
when:
m is molality of the solution
Kf is cryoscopic constant of water = 1.86 C/m
and ΔT is the change in melting point (T2 - 0 °C)
so, now we need to calculate the molality to substitute:
when the molality = moles NaCl / Kg of water
and when moles NaCl = mass / molar mass
= 2.5 g / 58 g/mol
= 0.043 mol
∴ Kg water = volume *density /1000
= 230 mL * 1 g/mL / 1000
= 0.23 Kg
∴ molality = 0.043 / 0.23 =0.187 M
by substitution:
T2-0°C = - 0.187 * 1.86
∴T2 = - 0.348 °C
Well, there are 6.02 X 10^23 Ions of Cu+2 in 1 mol of Cu+2, so simply divide 3.01 X 10^23 ions of Cu^+2 by Avogadro's number to find the number of moles for the copper II ions.
